Drought resistance of soft spring wheat varieties of different ecological and geographical origins in the Forest Steppe of Ukraine

Abstract

Wheat is one of the most important crops and the basis of human food and food security. Significant climate changes in recent years directly affect the formation of the level of wheat productivity. Therefore, the creation of varieties with increased resistance to drought at the initial stages of organogenesis, as well as the ability to form a high level of productivity in arid conditions is an urgent task in the modern selection of crops. The research aims to evaluate the level of drought tolerance wheat varieties different methods and to identify sources for involvement in crossbreeding during the selection of drought tolerance. Laboratory and field methods were used to study the researched varieties in response to drought: germination of seeds in a sucrose solution and determination of drought resistance indices by yield level. Varieties of spring wheat of different ecological and geographical origins have an increased productive potential in the conditions of the central part of the Forest Steppe of Ukraine. A wide range of variability in the degree of drought sensitivity of spring wheat was established. Varieties that have increased resistance to drought and can form a sufficient level of productivity under stress factors have been identified: Leguan (Czech Republic) and Koksa (Poland). The obtained results prove the possibility of combining in one variety an increased level of drought resistance and yield by classical breeding methods. According to the correlation coefficient between the productivity index and other studied indices of drought resistance, the effectiveness of using the Geometric Mean (proportional average) Productivity (GMP), Stress Tolerance Index (STI) and Yield Stability Index (YSI) indices in further breeding practice was noted. The practical research significance is determined by the combination of different methods for determining drought tolerance in crop breeding allowing for an objective assessment of resistance to stress factors and determination of viability at the initial stage of plant growth and development under the influence of the limiting factor – moisture